Researchers develop health-screening nanodevice

March 28, 2008 Arizona State University researcher Wayne Frasch has designed a method of DNA detection that is faster and more portable than any other current model. The result is a biosensing nanodevice that could transform security screening and health testing.

The work is based on the enzyme F1–adenosine triphosphatase (F1– ATPase). It was through a detailed study of the rotational mechanism of the F1–ATPase, which operates like a three–cylinder Mazda rotary motor, that Frasch conceived of a way to take this tiny biological powerhouse and couple it with science applications outside of the human body by "arming" it with an optical probe (gold nanorod) that can then be configured to emit a microscopic red signal when it detects a single molecule of target DNA

The DNA detector can be used to identify anthrax, cancer and Staphylococcus aureus – providing a significant tool in areas such as health screening. A prototype of the tissue-box sized device is currently being developed, and the method is being extended to detect protein at the single molecule level – an ability that will further distinguish it from competitors. Unlike DNA, proteins cannot be amplified artificially for detection purposes.

“Studies with the F1-ATPase in my laboratory show that since it can detect single DNA molecules, it far exceeds the detection limits of conventional PCR (polymerase chain reaction) technology,” said Frasch.

An article by Frasch and his colleagues – “Single-molecule detection of DNA via sequence–specific links between F1–ATPase motors and gold nanorod sensors” - was published in the journal Lab on a Chip, and appeared in the journal Chemical Biology. He is establishing a local company to produce the instrument.

“Rapid and sensitive biosensing of nucleic acids and proteins is vital for the identification of pathogenic agents of biomedical and bioterrorist importance,” said Frasch. “It also provides a new avenue through which to analyze genotypes and forensic evidence.”